Ore-separator



(No Model.) v a sheets sheet 1. E. W. STEPHENS Ore Separator.

No. 236,730. Patented Jan. 18, 1881.-

3 SheetsSheet 2.

(No Model.)

B. W. STEPHENS.

Ore Separator.

No. 236,730. Patented Jan. 18, 188i.

All

MPEI'ERS. PHOTOMTMOGRAPHER, WASHINGTON. D. c

EDWARD W. STEPHENS, OF SAN FRANCISCO, CALIFORNIA.

ORE-SEPARATOR.

SPECIFICATION forming part of Letters Patent No. 236,730, dated January 18, 1881.

Application filed April 9, 1880.

To all whom it may concern Be it known that I, EDWARD W. STEPHENS, of the city and county of San Francisco, and State of California, have invented an Improvement in Ore-Concentrators; and I do hereby declare the following to be a full, clear, and exact description thereof.

My invention relates to certain improvements in that class of concentrators and separators known as dry concentrators, in which a stratification of the substances to be concentrated first takes place by the action of a blast of air, and a separation of the strata is effected by the employment of knives and conveyingchutes.

My present invention is an improvement upon my former patent, dated February 18, 1879; and it consists in certain details of construction, as hereinafter described and claimed.

Referring to the accompanying drawings for a more complete explanation of my invention, Figure 1 is a view of my apparatus. Fig. 2 is a longitudinal section taken in a vertical plane. Fig. 3 is an enlarged section of the discharge portion of the apparatus. Figs. 4 and 5 show the crank-adjusting device. Figs. 6, 7 and 8 are detail views illustrative of the invention.

In my former patent I have shown a horizontally-moving ore-bed in combination with a vertically-moving blast-plate, which is situated directly beneath the moving bed, and which forces a body of air up through the orebed and the body of ore or other material which may be upon it, so that stratification and concentration of the material take place while the moving bed carries the material along to the point of discharge. In carrying out this principle practically I have found that some modifications in the apparatus will (No model.)

The blast-plate B may be of any suitable or desired shape; but I make it preferably of the same form and dimensions as the ore-bed,and it is actuated by a crank or eccentric and 21- pi tman, as will be more fully explained hereinafter. This blast-plate moves like a piston within its chamber D, fitting it closely, and it may be provided with air-valves E, opening upwardly, as described in my former patent, so that when the. plate is drawn downward these valves will open upward and admit air above the plate, and this air will be forcibly ejected through the ore-bed by the upward movement of the plate. The packing prevents any air from escaping at the sides, and as the blast-plate chamber is of the same size as the ore-bed, all parts of the latter receive the direct force of the air-blast.

In the construction of my ore-bed I have shown a finely-perforated plate, a, of gauze or punched metal, having cloth or canvas 1) stretched overit. Upon this is placed a guard, c, of wire-gauze, and the sand or pulverized ore is received upon this bed from a hopper, F, and is evenly distributed over the surface by the rapid and continual action of the airblast. The ore-bed in no sense acts as a screen, but simply as a support for the ore, with minute perforations to allow the air to pass, but to prevent any passage of ore or dust. This is really effected by the cloth or other fabric, while the gauze simply acts as a guard.

The movement of the blast-plate may be produced by cams and a spring, as shown in my former patent. I have shown in the present case an eccentric crank or wrist pin, G, turning in a box, H. The horizontal edges of this box are grooved or otherwise adapted to allow the box to move laterally in the frame I, and a stem or pitman, J, secured rigidly to this frame, passes through a guide, K, and is secured to the lower part of the blast-plate. The crank or wrist pin G is actuated by a shaft, L, driven by suitable power, and a disk, M, to which the pin is connected by means of an intervening plate, N. The wrist-pin is firmly secured to this plate, projecting from its face, and the plate serves to regulate the throw of the wrist-pin, and through it that of the blastplate, as follows The plate N has a pin passing through one side and into the disk M, so

that it may turn about this pin. A set screw or screws pass through a slot or slots in the plate N and into the plate M, and the plateN may thus be moved about its fixed pin, so as to set the crank-pin nearer to or farther from the center or line of the shaft, and held at the desired point by the set-screw passing through the slot. This regulates the throw of the crank and the movement of the blast-plate.

In running this machine a rapid motion is given to the blast-plate, and the air is thus taken into the chamber D through the valves and ejected through the ore-bed in a succession of quick pufl's or blasts, and the peculiar construction of the ore-bed causes it to offer such a resistance that the air is somewhat compressed before it can pass through, which renders its action more efficient. The sand, ore, or other material carrying gold or other valuable substance which it is desired to sepa rate is placed in the feed-hopper E, which has a long narrow slot at its lower edge extending the full width of the ore-bed, so that the sand is evenly distributed over the surface of the bed. The action of the intermittent blasts or pulsations of air which are forced up through the orebed and the superincumbent material throws this material up, and as it falls back it becomes stratified, the heavier and more valuable port-ions settling to the bottom, while the lighter portions remain upon the surface, or near the top. This action is greatly assisted by a partial vacuum which takes place between each upward blast by the downward movement of the blast-plate, this vacuum being produced and its amount determined by the resistance to the opening'of the valves E, caused either by their weight or elasticity, or in any suitable manner and to any amount desired. In some cases I. find it preferable to produce this action by omitting the valves E and making the blast-plate tight or close. The sides of the chamber D are then perforated with slots or holes I] at a point which will just allow the blast-plate to pass below them at its lowest point. it will be seen that by this construction no air can be admitted above the blast-plate, except by drawing it through the ore-bed and ore or sand, until the blast-plate has descended below these holes, and the close texture of the ore-bed will offer so much resistance to the entrance of air through it that a considerable vacuum will be formed by each downward stroke of the blastplate. WVhen the plate reaches its lowest point a new body of air will fill theehamber through these holes, in readiness for the next upward stroke. The action in this case will be similar to that which takes place when the valves have a considerable tension or resistance to being readily opened. This vacuum acts to bring the material down upon the bed sharply and allows of a much higher rate of speed and a more complete stratification than when gravitation alone is depended upon to bring the material down.

In order to regulate the discharge of the different strata, I employ dividing knives or gates P Q, at the discharge end of the machine, which is formed with a downward inclination, as shown. The ore-bed proper may remain horizontal or have a slight incline forward. The gate or knife P works vertically in front of a serrated stationary plate, It, and is adjusted to discharge with any desired rapidity by means of screws S. The upper or overflow knife or gate, Q, has an inclined discharge-lip, as shown, and slotted flanges T, by which it is secured to the ore-bed frame, its vertical il(1-' justmeut being secured by clampscrews U.

From each of these discharge-gates chutes lead to different receptacles, and the upper and lower strata may be separated with any desired degree of accuracy. The valves E open toward the rear, and their action causes a peculiar movement of the air through the ore-bed toward the discharge, which causes the ore to move in that direction during its tossing movements.

This apparatus is especially valuable for the purpose of concentrating gold-bearing sand, black sand, and sulphurets in localities where such sands are found at great distances from water, and when it is not convenient or proper to use water.

Having thus described my invention, what I claim as new, and desire to secure by Letters- Patent, is

1. The blast-chamber D, having the inlet openings or valves and the rigid reciprocating piston B and mechanism to move it vertically within the chamber, as shown, in combination with a continuous ore-bed, consisting of the fabric I) and its guards at 0, extending entirely across the blast-chamber, adapted to receive the ore at one side and discharge it at the other, substantially as herein described.

2. The stationary foraminous ore-bed, consistiug of the guards to c and the interposed cloth or other fabric b, united as shown, in combination with the air-blast chamber D, with its rigid piston or plate B and mechanism to reciprocate it vertically in the chamber, and said plate B being provided with the slots or perforations and spring-valves E, having a tension whereby a partial vacuum is produced between the bed-plate and the orebed during the first portion of the downward movement of the blast-plate, substantially as herein described.

In witness whereof I have hereunto set my hand.

EDWARD W. STEPHENS.

Witnesses:

FRANK A. BROOKS, S. H. NoURsE. 

